Question

Write down the names of compounds represented by the following formulae and also write the anion, cation.

 i) Al₂(SO₄)₃

 ii) CaCl₂

iii) K₂SO₄ 

iv) KNO₃ 

v) CaCO₃

Answer 1

Formula	Cation	Anion	Compound Name
Al2(SO4)3	Al3+	SO42-	Aluminium sulphate
CaCl2	Ca2+	Cl-	Calcium chloride
K2SO4	K+	SO42-	Potassium sulphate
KNO3	K+	NO-3	Potassium nitrate
CaCO3	Ca2+	CO42-	Calcium carbonate

Answer 2

(i) Al2(SO4)3

Aluminium sulphate: Aluminium sulfate is an industrial chemical used as a flocculating agent in the purification of drinking water

(ii) CaCl2

Calcium chloride: Calcium chloride is widely used as an additive in plastics, wastewater treatment plants

(iii) K2SO4

Potassium sulphate: Potassium sulfate is the preferred fertilizer for specific kinds of crops

(iv) KNO3

Potassium nitrate: It is a strong oxidizer used especially in making gunpowder, as a fertilizer, and in medicine.

(v) CaCO3

Calcium carbonate: It is a medication used to prevent or treat low blood calcium levels and also an antacid.